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1.
Chromosome Res ; 31(1): 2, 2023 01 20.
Article in English | MEDLINE | ID: mdl-36662301

ABSTRACT

Karyotypes are generally conserved between closely related species and large chromosome rearrangements typically have negative fitness consequences in heterozygotes, potentially driving speciation. In the order Lepidoptera, most investigated species have the ancestral karyotype and gene synteny is often conserved across deep divergence, although examples of extensive genome reshuffling have recently been demonstrated. The genus Leptidea has an unusual level of chromosome variation and rearranged sex chromosomes, but the extent of restructuring across the rest of the genome is so far unknown. To explore the genomes of the wood white (Leptidea) species complex, we generated eight genome assemblies using a combination of 10X linked reads and HiC data, and improved them using linkage maps for two populations of the common wood white (L. sinapis) with distinct karyotypes. Synteny analysis revealed an extensive amount of rearrangements, both compared to the ancestral karyotype and between the Leptidea species, where only one of the three Z chromosomes was conserved across all comparisons. Most restructuring was explained by fissions and fusions, while translocations appear relatively rare. We further detected several examples of segregating rearrangement polymorphisms supporting a highly dynamic genome evolution in this clade. Fusion breakpoints were enriched for LINEs and LTR elements, which suggests that ectopic recombination might be an important driver in the formation of new chromosomes. Our results show that chromosome count alone may conceal the extent of genome restructuring and we propose that the amount of genome evolution in Lepidoptera might still be underestimated due to lack of taxonomic sampling.


Subject(s)
Butterflies , Animals , Butterflies/genetics , Wood , Chromosome Mapping , Genome , Synteny , Sex Chromosomes , Evolution, Molecular
2.
Transplantation ; 72(6): 1128-37, 2001 Sep 27.
Article in English | MEDLINE | ID: mdl-11579312

ABSTRACT

BACKGROUND: Recent studies have shown some efficacy using monotherapy with monoclonal antibodies (mAb) against CD80 and CD86 receptors after life-supporting renal transplantation in non-human primates. Our study was designed to evaluate the efficacy of combinations of the same mAbs with either microemulsion cyclosporine (CsA) or steroids. METHODS: Unilateral renal transplantation was performed in 16 blood group-matched and MLR-mismatched cynomolgus monkeys that were assigned to four different treatment groups. All monkeys in groups I, II, and IV were treated with the combination of a CD80 (h1F1) and CD86 (h3D1) mAb given at 20 mg/kg each preoperatively, then 5 mg/kg at weekly intervals starting postoperative (po) day 0 until poday 56 (9 doses). In group I the animals (n=4) were treated with mAbs only. In group II (n=4) mAbs were combined with a CsA regimen adjusted daily to maintain target 24 hr trough levels of 150-300 ng/ml CsA for poday 0 to poday 56. In group III (n=4) the animals received CsA monotherapy according to the same regimen as group II. In group IV methylprednisone was administered at 2 mg/kg IV on poday 0-2, then at 0.5 mg/kg/day prednisone per gavage that was and tapered to 0.2 mg/kg/day on which they were maintained until poday 56. All animals were off all immunosuppressive treatment after poday 56 and were then followed until poday 119. RESULTS: The mean survival of groups I-IV was 74 (range 9-119 days), 113 (96-119 days), 39 (22-71 days), and 79 days (6 to 119), respectively. All animals in group I showed clinical evidence of acute severe rejection (fever, creatinine increase, anuria) within the first week posttransplant, including those that retained renal function until poday 119. Only one animal in group II had a moderate clinical rejection during the treatment period and three of four animals survived the intended follow-up period. All animals in group III had multiple biopsy proven or severe clinical rejection episodes within the first 21 days and only one animal survived beyond poday 40. Moderate or severe acute rejection was diagnosed in three of four animals of group IV within the first 28 days post transplant and only one animal survived until poday 119. CONCLUSION: Our data show that combining a calcineurin inhibitor or prednisone with mAbs designed to block costimulatory signals does not antagonize the immunosuppressive efficacy of these mAbs. In addition, combining CsA with mAbs directed against the CD80 and CD86 receptors significantly prolongs graft survival when compared to CsA monotherapy. Therefore clinical trials of humanized mAbs to CD80 and CD86 used in combination with conventional immunosuppression can be considered.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Antigens, CD/immunology , B7-1 Antigen/immunology , Cyclosporine/administration & dosage , Graft Survival/drug effects , Immunosuppressive Agents/administration & dosage , Kidney Transplantation , Membrane Glycoproteins/immunology , Steroids/administration & dosage , Animals , Antibodies, Monoclonal/blood , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/therapeutic use , B7-2 Antigen , Biological Availability , Cyclosporine/pharmacokinetics , Cyclosporine/therapeutic use , Drug Combinations , Graft Rejection/epidemiology , Graft Rejection/pathology , Humans , Immunosuppressive Agents/pharmacokinetics , Immunosuppressive Agents/therapeutic use , Incidence , Macaca fascicularis , Male , Steroids/therapeutic use , Survival Analysis , Time Factors
3.
Qual Assur ; 9(3-4): 155-64, 2001.
Article in English | MEDLINE | ID: mdl-12553078

ABSTRACT

The EPA Supersites Research Program needs consistency of metadata and data structures to facilitate information sharing among investigators, analysts, and ultimately secondary data users. Under the auspices of NARSTO a successful mechanism was created to develop and implement reporting standards. The development effort included working closely with Supersites data coordinators, investigators, and technical experts, and also leveraging from existing data standards and practices. Overall, the standards are getting good acceptance from the atmospheric research community.


Subject(s)
Environmental Monitoring/standards , Hazardous Waste , Research Design/standards , United States Environmental Protection Agency/organization & administration , Cities , Database Management Systems , Documentation/standards , Forms and Records Control , Guideline Adherence , Humans , United States
4.
J Virol ; 74(19): 8876-83, 2000 Oct.
Article in English | MEDLINE | ID: mdl-10982330

ABSTRACT

Retroviruses are believed to induce tumors by acting as insertional mutagens that activate expression of cellular protooncogenes. Indeed, almost 90% of mouse mammary tumor virus (MMTV)-induced mammary tumors in C3H/He mice show upregulation of Int protooncogenes. We have analyzed three different MMTV variants [MMTV(C3H), MMTV(HeJ), and a genetically engineered MMTV hybrid provirus (HP)] for tumorigenicity in mice from two distinct genetic backgrounds. All three viruses were tumor causing in BALB/cJ mice. However, only MMTV(C3H), but not MMTV(HeJ) or HP, induced mammary tumors in C3H/He mice. All of the viruses were infectious on either background and up-regulated expression of Int genes in tumors they induced. Like HP, MMTV(HeJ) was found to be a genetic recombinant between endogenous Mtv1 provirus and exogenous MMTV(C3H). Sequence comparison of MMTV variants linked the tumorigenicity of MMTV(C3H) to the gag region of the retrovirus.


Subject(s)
Genes, gag , Mammary Neoplasms, Experimental/virology , Mammary Tumor Virus, Mouse/genetics , Amino Acid Sequence , Animals , Female , Gene Expression Regulation, Neoplastic , Gene Expression Regulation, Viral , Mammary Neoplasms, Experimental/etiology , Mammary Tumor Virus, Mouse/pathogenicity , Mice , Mice, Inbred C3H , Molecular Sequence Data , Sequence Alignment
5.
Transplantation ; 69(4): 488-96, 2000 Feb 27.
Article in English | MEDLINE | ID: mdl-10708100

ABSTRACT

BACKGROUND: In previous studies of cynomolgus monkey lung allograft recipients, we demonstrated significant immunosuppressive efficacy but reduced tolerability after combined treatment with high doses of microemulsion cyclosporine (CsA) and SDZ RAD (40-O-(2-hydroxyethyl)-rapamycin). The current study was designed to compare efficacy and tolerability of a combination of low-dose CsA and high-dose SDZ RAD (CTL group) to triple therapy using the chimeric anti-interleukin-2 (IL-2) receptor (CD25) monoclonal antibody (mAb) basiliximab (anti-IL-2 receptor mAb) for induction therapy (basiliximab: 5 mg intravenously on days 0 and 4) plus low-dose CsA and low-dose SDZ RAD for maintenance immunosuppression (CD25 group). CsA and anti-IL-2 receptor mAb are drugs that reduce cytokine synthesis and block IL-2-mediated lymphocyte stimulation, respectively. SDZ RAD blocks lymphocyte stimulation by other cytokines (e.g., IL-15) that are not inhibited by anti-IL-2 receptor mAb. METHODS: Twelve unilateral lung transplants were performed. Recipients were observed for 49 days by daily weight assessment, hemograms, blood chemistries, radiographs, and lung biopsies. Monkeys were euthanized before day 49 in the event of excessive weight loss (>25%) or organ failure. Target CsA trough levels were 100-200 ng/ml. Target SDZ RAD trough levels in the CTL group (no mAb) were 20-40 ng/ml, and 10-20 ng/ml in the CD25 group. RESULTS: None of the monkeys in the CD25 group needed to be euthanized early due to signs of drug toxicity. In contrast, four monkeys in the CTL group were sacrificed on days 28-35 as a result of excessive weight loss (n=3) and renal functional impairment (n=1). Three recipients in the CD25 group were euthanized on days 36, 38, and 46 as a result of persistent high fever associated with severe rejection. The median animal survival in the CTL group was 32 vs. 46 days in the CD25 group (P<0.04). The only two long-term survivors in the CTL group showed moderate rejection at day 49. The median rejection scores at day 14 (A0) and day 28 (A2) were identical in the two groups, despite the fact that the mean SDZ RAD trough level was significantly lower in the CD25 group (CTL: 38+/-3 ng/ml, CD25: 18+/-2 ng/ml, P<0.0001). After basiliximab levels fell below the minimum therapeutic level (1 mg/ml) on day 28, the median rejection score at day 49 increased to A4 in the CD25 group. CONCLUSION: This is the first study to combine an anti-IL-2 receptor mAb with a drug from the rapamycin class plus CsA. Our study shows that induction therapy with basiliximab enabled SDZ RAD blood levels to be significantly reduced, which led to improved tolerability without the penalty of increased rejection.


Subject(s)
Lung Transplantation/immunology , Animals , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/therapeutic use , Autopsy , Basiliximab , Biopsy , Body Weight , Bronchoscopy , Creatinine/blood , Cyclosporine/administration & dosage , Cyclosporine/pharmacokinetics , Cyclosporine/therapeutic use , Dose-Response Relationship, Drug , Drug Synergism , Drug Therapy, Combination , Emulsions , Everolimus , Graft Rejection/prevention & control , Immune Tolerance/drug effects , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/therapeutic use , Lung/pathology , Macaca fascicularis , Male , Microchemistry , Postoperative Period , Receptors, Interleukin-2/immunology , Recombinant Fusion Proteins/immunology , Sirolimus/administration & dosage , Sirolimus/analogs & derivatives , Sirolimus/therapeutic use , Tissue Donors
6.
Transplantation ; 69(1): 76-86, 2000 Jan 15.
Article in English | MEDLINE | ID: mdl-10653384

ABSTRACT

BACKGROUND: We studied the efficacy and tolerability of combined immunosuppressive therapy with cyclosporine A microemulsion (Neoral) plus the macrolide SDZ RAD 40-0 (2-hydroxyethyl) rapamycin (RAD) in a stringent cynomolgus monkey lung graft model in comparison with cyclosporine or SDZ RAD monotherapy. METHODS: Thirty-nine cynomolgus monkeys received mixed lymphocyte reaction (MLR) mismatched unilateral lung transplants. Immunosuppressants were administered orally as single daily doses. The observation period was 28 days and follow-up included serial trough blood drug concentrations measured by high performance liquid chromatography/mass spectrometry, blood analyses, chest radiographs, open lung biopsies, as well as tissue drug concentrations and graft histology at necropsy. RESULTS: Graft biopsies in monkeys treated with vehicle (n=4), Neoral (day 1-7: 150 mg/kg/day; day 8-28: 100 mg/kg/day; n=6; mean +/- SE trough level (MTL): 292+/-17 ng/ml) or SDZ RAD monotherapy (1.5 mg/kg/day; n=6; MTL: 15+/-1 ng/ml) showed severe rejection. Coadministration in two transplant monkeys of Neoral (150/100 mg/kg/day) and SDZ RAD (1.5 mg/kg/day) caused their early death. In both animals, SDZ RAD blood levels were more than 5-fold higher than under monotherapy (MTL: 82+/-18 ng/ml). Simultaneous administration (n=6) of Neoral (150/100 mg/kg/day; MTL: 217+/-16 ng/ml) and SDZ RAD (0.3 mg/kg/day; MTL: 24+/-2 ng/ml) improved graft outcome (mild rejection). Side effects included renal failure (n=2) and seizures (n=1). Three monkeys survived to day 28. In this group the MTL for cyclosporin was 143+/-13 and for RAD 38+/-3. Staggered treatment completely prevented rejection in four of six grafts. However, five of six monkeys had moderate to severe diarrhea. In a concentration-controlled trial of simultaneously administered Neoral and SDZ RAD in transplant monkeys (target SDZ RAD MTL: 20-40 ng/ml; cyclosporine MTL: 100-200 ng/ml) all six monkeys survived with improved drug tolerability and an average biopsy score of mild rejection. CONCLUSION: Combination of orally administered SDZ RAD and Neoral showed excellent immunosuppressive efficacy in a stringent lung transplant model. The drug interaction and the narrow therapeutic index of this drug combination required careful dose adjustments to optimize tolerability and efficacy.


Subject(s)
Cyclosporine/therapeutic use , Immunosuppressive Agents/therapeutic use , Lung Transplantation , Sirolimus/analogs & derivatives , Animals , Blood/metabolism , Bronchoscopy , Dose-Response Relationship, Drug , Drug Therapy, Combination , Everolimus , Graft Rejection/pathology , Graft Rejection/prevention & control , Lung/pathology , Lung/physiopathology , Macaca fascicularis , Sirolimus/blood , Sirolimus/therapeutic use
7.
J Heart Lung Transplant ; 18(7): 714-24, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10452349

ABSTRACT

BACKGROUND: The diagnosis of acute rejection in lung transplantation generally relies on transbronchial biopsies. This invasive procedure may be associated with bronchial bleeding or pneumothorax and may not be feasible in patients with severely compromised lung function. The hypothesis of the current study was that histopathological findings of donor bronchial segments implanted into the subcutaneous tissue of lung allograft recipients would predict lung tissue rejection scores, thus providing the clinician with an alternate source of information. METHODS: Unilateral left lung transplantation was performed in 34 cynomolgus monkeys as part of a drug efficacy study. After completion of the transplant procedure, 4 bronchial ring segments of the explanted recipient left lung and 4 bronchial ring segments of the non-transplanted right donor lung were implanted subcutaneously in the abdominal region. Lung allograft rejection was evaluated by open lung biopsies of the allograft performed on postoperative (PO) Day 14 and during sacrifice on PO Day 28. At the time of each biopsy, 2 donor and 2 recipient subcutaneous bronchial rings were explanted. Histologic evaluation of the lung tissue samples was performed according to the working formulation of the International Society for Heart and Lung Transplantation. Bronchial rings were independently evaluated by assessing the degree of airway narrowing; percentage of intact epithelial coverage as well as its specific histology (respiratory ciliated, flattened cuboidal, squamous); presence of lymphocytes, macrophages or spindle cells; and presence of peribronchial inflammation, luminal fibrosis, lymphocytic bronchitis or luminal mucous. Statistical analysis was performed by logistic regression. RESULTS: In the recipient bronchial rings, there was no evidence of airway narrowing. There was 98% epithelial coverage, 71% that were respiratory ciliated cells, and there was no inflammation. Donor bronchial rings showed no airway narrowing for monkeys with grade A0 to A2 rejection in tissue biopsies and a maximum narrowing (41.2%) with A4 rejection. Epithelial cell coverage was approximately 100% with grade A0-A2 and 44+/-11% with A4 rejection. Lymphocytic bronchitis was most severe in A4 rejection and minimal in A0 to A2 rejection. By logistic regression analysis, independent predictors of a likelihood of rejection were the degree of airway obliteration, the percentage of epithelial cell coverage, the degree of lymphocytic bronchitis and the product of respiratory and flattened cuboidal cell coverage. CONCLUSIONS: The current data show that histologic alterations of subcutaneously implanted donor bronchial rings correlate with lung tissue biopsy scores based on the ISHLT working formulation. Because subcutaneous bronchial rings can be explanted under local anesthesia, they may provide useful information for the diagnosis of acute allograft rejection in patients with impaired lung function, patients that obtaining lung tissue samples may not be feasible.


Subject(s)
Bronchi/pathology , Bronchi/transplantation , Disease Models, Animal , Graft Rejection/pathology , Lung Transplantation/pathology , Transplantation, Heterotopic/pathology , Acute Disease , Animals , Biopsy , Chi-Square Distribution , Immunosuppression Therapy/methods , Logistic Models , Lung/pathology , Lung Transplantation/methods , Lung Transplantation/statistics & numerical data , Macaca fascicularis , Male , Skin , Statistics, Nonparametric , Transplantation, Heterotopic/statistics & numerical data , Transplantation, Homologous
8.
Biotechniques ; 20(4): 652-7, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8800685

ABSTRACT

A method is described in which the relative number of adherent cells in multi-well tissue-culture plates is assayed by staining the cells with Giemsa and capturing the image of the stained cells with a video camera and charged-coupled device. The resultant image is quantified using the associated video imaging software. The method is shown to be sensitive and reproducible and should be useful for studies where quantifying relative cell numbers and/or proliferation in vitro is required.


Subject(s)
Cell Culture Techniques/instrumentation , Microscopy, Video/methods , Animals , CHO Cells/cytology , Cell Count , Cell Culture Techniques/methods , Cell Division , Cricetinae , Staining and Labeling , Transfection
10.
Mol Immunol ; 29(1): 21-30, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1731188

ABSTRACT

Recombinant DNA techniques were used to clone and express the FV portion of MOPC315, a mouse myeloma protein with a high affinity for 2,4-dinitrophenyl (DNP). The FV fragment consists of a heterodimer of heavy and light chain variable domains (VH and VL). Two separate bacterial plasmid constructs, containing either a variable region cDNA for the light chain or a variable region synthetic gene for the heavy chain demonstrated high levels of expression (150-200 mg/L) under control of the bacteriophage T7 promoter. Recombinant chains were initially recovered as inclusion bodies and then dissolved separately in 8 M urea, combined together, and refolded by subsequent chaotrope removal. Biologically active FV was affinity purified from the chain mixture by specific binding to DNP-lysine-Sepharose. Yields of active material as high as 20% were obtained with activity confirmed by fluorescence quench analysis. The purified FV displayed a binding affinity of 4.8 +/- 0.3 x 10(-7) M which was identical to the native FV. Chimeric FVs composed of recombinant and native chain mixtures yielded similar results. Recombinant MOPC315 FV activity was also obtained using a single chain construct (sFV), in which recombinant VH and VL were linked via a (Gly4Ser)3 spacer region. Binding affinity of the sFV was shown to be the same as the recombinant and native FVs. The ease of purification and characterization of active MOPC315 as the recombinant and native FVs. The ease of purification and characterization of active MOPC315 FV makes this system useful in the study of the optimization of antibody production in bacteria.


Subject(s)
Immunoglobulin Variable Region/genetics , Myeloma Proteins/genetics , Amino Acid Sequence , Animals , Base Sequence , Chromatography, Affinity , Cloning, Molecular , Dinitrobenzenes/immunology , Dinitrobenzenes/metabolism , Escherichia coli , Genes, Immunoglobulin , Immunoglobulin A/genetics , Mice , Molecular Sequence Data , Oligonucleotides/chemistry , Protein Conformation , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Solubility
11.
Am J Med ; 84(3 Pt 1): 513-6, 1988 Mar.
Article in English | MEDLINE | ID: mdl-3348251

ABSTRACT

Five patients with hereditary spherocytosis diagnosed in their seventh to ninth decades of life are presented. These patients are remarkable for absent or mild clinical manifestations of disease. Splenectomy is the recommended treatment for hereditary spherocytosis to avoid the complications of aplastic or hemolytic crisis. When the diagnosis is made in the elderly, the treatment of choice may be careful observation with folic acid supplementation rather than splenectomy. This recommendation is based on the incidence of complications of splenectomy in the elderly in comparison to the severity and incidence of complications from the disease itself.


Subject(s)
Spherocytosis, Hereditary , Age Factors , Aged , Aged, 80 and over , Female , Folic Acid/therapeutic use , Humans , Male , Middle Aged , Spherocytosis, Hereditary/diagnosis , Spherocytosis, Hereditary/drug therapy
12.
Appl Environ Microbiol ; 50(4): 1007-13, 1985 Oct.
Article in English | MEDLINE | ID: mdl-4083871

ABSTRACT

Relatively rapid methods for the determination of relative genome molecular mass (Mr) and the estimation of plasmid copy number have been developed. These methods are based on the ability of the Bio-Rad high-pressure liquid chromatography hydroxylapatite column to separate and quantify single-stranded DNA, double-stranded DNA, and plasmid DNA. Genome Mr values were calculated from reassociation kinetics of single-stranded DNA as measured with the hydroxylapatite column. Bacteriophage T4 DNA was used to establish a C0t (moles of nucleotides times seconds per liter), or standard reassociation value. From this C0t value, C0t values for Escherichia coli B, Beggiatoa alba B18LD, and Streptomyces coelicolor were determined by comparative calculations. From those calculated C0t values, the Mr values of 1.96 X 10(9) for E. coli, 2.02 X 10(9) for B. alba, and 3.28 X 10(9) for S. coelicolor were estimated. Plasmid concentration was determined from cleared lysates by comparing the integrated area under the phosphate buffer-eluted plasmid peak to values obtained with known amounts of plasmid. The plasmid copy number was estimated by multiplying the ratio between the amounts of plasmid and chromosomal DNA by the ratio between the Mr values of the chromosome and the plasmid. A copy number of 29 was obtained from a culture of E. coli HB101 harboring pBR322 grown to a culture density of 1.6 X 10(9) CFU . ml-1.


Subject(s)
DNA, Bacterial/genetics , DNA, Bacterial/isolation & purification , Genes, Bacterial , Plasmids , Streptomyces/genetics , T-Phages/genetics , Thiotrichaceae/genetics , Chromatography, High Pressure Liquid , DNA, Single-Stranded/genetics , DNA, Viral/isolation & purification , Genes, Viral , Molecular Weight
13.
Am J Clin Pathol ; 84(2): 248-51, 1985 Aug.
Article in English | MEDLINE | ID: mdl-4025231

ABSTRACT

A case report of a healthy 33-year-old man with Mycoplasma pneumoniae pneumonia who concomitantly had the acquired Pelger-Huet anomaly develop is presented. Up to 31% of his total white blood cell count was comprised of Pelger-Huet cells at the height of his clinical illness. The Pelger-Huet cell count returned to 0% after doxycycline therapy and resolution of the pneumonia. No other explanation for the Pelger-Huet anomaly could be determined. A review of the pertinent hematologic literature is included.


Subject(s)
Pelger-Huet Anomaly/blood , Pneumonia, Mycoplasma/blood , Adult , Humans , Male , Pelger-Huet Anomaly/complications , Pneumonia, Mycoplasma/complications
14.
Appl Environ Microbiol ; 47(4): 868-9, 1984 Apr.
Article in English | MEDLINE | ID: mdl-6372691

ABSTRACT

Growth of the four methanogens investigated was inhibited by chloramphenicol-3-acetate; therefore, introduction of chloramphenicol acetyltransferase-encoding genes should not confer chloramphenicol resistance on these methanogens. Reduction of the aryl nitro group of chloramphenicol produced a compound which did not inhibit the growth of these methanogens.


Subject(s)
Acetyltransferases/genetics , Chloramphenicol/toxicity , Euryarchaeota/drug effects , Chloramphenicol/analogs & derivatives , Chloramphenicol O-Acetyltransferase , Drug Resistance, Microbial , Escherichia coli/drug effects , Euryarchaeota/enzymology , Euryarchaeota/genetics , Methanol/metabolism , Species Specificity
15.
J Bacteriol ; 148(2): 572-83, 1981 Nov.
Article in English | MEDLINE | ID: mdl-6117547

ABSTRACT

The assimilation and metabolism of CO(2) and acetate by Beggiatoa alba strain B18LD was investigated. Although B. alba was shown to require CO(2) for growth, the addition of excess CO(2) (as NaHCO(3)) to the medium in a closed system did not stimulate growth. Approximately 24 to 31% of the methyl-labeled acetate and 38 to 46% of the carboxyl-labeled acetate were oxidized to (14)CO(2) by B. alba. The apparent V(max) values for combined assimilation and oxidation of [2-(14)C]acetate by B. alba were 126 to 202 nmol min(-1) mg of protein(-1) under differing growth conditions. The V(max) values for CO(2) assimilation by heterotrophic and mixotrophic cells were 106 and 131 pmol min(-1) mg of protein(-1), respectively. The low V(max) values for CO(2) assimilation, coupled with the high V(max) values for acetate oxidation, suggested that the required CO(2) was endogenously produced from acetate. Moreover, exogenously supplied acetate was required by B. alba for the fixation of CO(2). From 61 to 73% of the [(14)C]acetate assimilated by washed trichomes was incorporated into lipid. Fifty-five percent of the assimilated [2-(14)C]acetate was incorporated into poly-beta-hydroxybutyric acid. This was consistent with chemical data showing that 56% of the heterotrophic cell dry weight was poly-beta-hydroxybutyric acid. Succinate and CO(2) were incorporated into cell wall material, proteins, lipids, nucleic acids, and amino and organic acids, but not into poly-beta-hydroxybutyric acid. Glutamate and succinate were the major stable products after short-term [1-(14)C]acetate assimilation. Glutamate and aspartate were the first stable (14)CO(2) fixation products, whereas glutamate, a phosphorylated compound, succinate, and aspartate were the major stable (14)CO(2) fixation products over a 30-min period. The CO(2) fixation enzymes isocitrate dehydrogenase (nicotinamide adenine dinucleotide phosphate; reversed) and malate dehydrogenase (nicotinamide adenine dinucleotide phosphate; decarboxylating) were found in cell-free extracts of both mixotrophically grown and heterotrophically grown cells. The data indicate that the typical autotrophic CO(2) fixation mechanisms are absent from B. alba B18LD and that the CO(2) and acetate metabolism pathways are probably linked.


Subject(s)
Acetates/metabolism , Carbon Dioxide/metabolism , Thiotrichaceae/metabolism , Glutamates/metabolism , Glutamic Acid , Isocitrate Dehydrogenase/metabolism , Malate Dehydrogenase/metabolism , NADP/metabolism , Succinates/metabolism , Succinic Acid , Thiotrichaceae/growth & development
16.
J Cell Sci ; 43: 93-102, 1980 Jun.
Article in English | MEDLINE | ID: mdl-7419628

ABSTRACT

The enzymic properties of adenylyl cyclase in purified membrane vesicles from human and boar spermatozoa are described. Plasma membrane vesicles, which appear to be right-side-out, show a marked increase in activity in the presence of the detergent Triton X-100, manganous ion and alkaline pH. Electron-microscope cytochemical assays indicated the presence of adenylyl cyclase in boar and human sperm plasma membranes and also within the axoneme of intact human spermatozoa. The significance and precautions in the evaluation of the cytochemical data are discussed.


Subject(s)
Adenylyl Cyclases/analysis , Spermatozoa/enzymology , Adenylyl Cyclases/metabolism , Animals , Cell Membrane/enzymology , Histocytochemistry , Humans , Hydrogen-Ion Concentration , Male , Microscopy, Electron , Swine
17.
Prep Biochem ; 8(5): 363-78, 1978.
Article in English | MEDLINE | ID: mdl-714884

ABSTRACT

A method for isolation of plasma membrane vesicles from human and boar spermatozoa using nitrogen cavitation is described. The purity of the preparations were assessed by electron microscopy, marker enzyme assay and the sedimentation characteristics of fused plasma membrane-acrosomal membrane vesicles in sucrose gradients. PAGE-SDS profiles of plasma membrane polypeptides from boar spermatozoa were significantly different from those of human spermatozoa. Differences in electrophoretic profiles of polypeptides from different regions of the spermatozooon were also observed.


Subject(s)
Spermatozoa/cytology , Acrosome , Animals , Cell Fractionation , Cell Membrane , Centrifugation, Density Gradient , Electrophoresis, Polyacrylamide Gel , Humans , Male , Methods , Microscopy, Electron , Nitrogen , Species Specificity , Swine
18.
Appl Environ Microbiol ; 34(3): 333-5, 1977 Sep.
Article in English | MEDLINE | ID: mdl-16345252

ABSTRACT

Ten species of myxobacteria were identified from samples from an alkaline bog and adjacent soils. The frequency of occurrence and the diversity of species were highest at the margin of the bog and were lowest in the center and bottom of the bog lake.

19.
J Am Diet Assoc ; 49(3): 202-3, 1966 Sep.
Article in English | MEDLINE | ID: mdl-5921142

Subject(s)
Copper , Food Analysis
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